Embodiments of the present disclosure generally relate to systems and methods for machining portions of an acoustic inlet barrel of an engine assembly, such as that of a jet aircraft.
Jet aircraft typically include one or more engines that may generate high levels of noise. For example, a fan case within a housing secured to a wing of an aircraft typically generates noise. Often, engine housings include one or more sound dampening structures that are used to absorb at least a portion of the noise generated by components of an engine. For example, an acoustic inlet barrel may be positioned at or proximate to an inlet of the engine housing upstream from a fan case.
Known acoustic inlet barrels are formed of composite materials, such as carbon-reinforced plastics, that are sandwiched around an acoustic core, such as a porous foam material. Often, an acoustic inlet barrel is formed of multiple pieces. For example, each acoustic inlet barrel may be formed of two or three pieces that are secured together through fasteners, such as bolts. The pieces are secured together to form the acoustic inlet barrel.
In order to secure the acoustic inlet barrel into a housing of an engine assembly, surfaces of the acoustic inlet barrel are machined so that they securely and precisely connect to portions of the housing. For example, an end surface of an acoustic inlet barrel is machined to securely and precisely connect to a lip joint or surface that connects to an outer surface of the housing. Similarly, an opposite end surface of the acoustic inlet barrel is machined to securely and precisely connect to an interior fan case within the housing. As can be appreciated, in order to accurately machine the surfaces of the acoustic inlet barrel, great care is taken to ensure that the acoustic inlet barrel is properly oriented and positioned prior to machining. In general, the process of identifying the proper surfaces for machining and accurately machining the surfaces is time and labor intensive. Moreover, because an initially-formed acoustic inlet barrel may have a degree of slack, surfaces of the acoustic inlet barrel may not be accurately machined. For example, during a machining process, portions of the acoustic inlet barrel may shift or otherwise move, which may lead to improperly machined surfaces.
Accordingly, a need exists for a system and method of positioning an acoustic inlet barrel prior to machining. Further, a need exists for a system and method of accurately machining surfaces of the acoustic inlet barrel.